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[PATCH v44 07/10] Split cluster.h to create repack_internal.h 403+ messages / 2 participants [nested] [flat]
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 403+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 403+ messages in thread
* [PATCH] Allow progress tracking of sub-commands. @ 2026-05-04 09:32 Antonin Houska <ah@cybertec.at> 0 siblings, 0 replies; 403+ messages in thread From: Antonin Houska @ 2026-05-04 09:32 UTC (permalink / raw) Some commands that support progress reporting run sub-commands, which also report their progress. The typical case is that REPACK builds indexes. Instead of disabling the progress tracking of the sub-commands, we can allow both the "parent" command and the sub-command to report their progress at the same time. --- contrib/file_fdw/file_fdw.c | 44 +++++++++++ src/backend/commands/indexcmds.c | 10 ++- src/backend/commands/repack.c | 14 +++- src/backend/utils/activity/backend_progress.c | 76 ++++++++++++++++--- src/backend/utils/activity/backend_status.c | 1 + src/backend/utils/adt/pgstatfuncs.c | 9 ++- src/include/utils/backend_status.h | 7 ++ 7 files changed, 142 insertions(+), 19 deletions(-) diff --git a/contrib/file_fdw/file_fdw.c b/contrib/file_fdw/file_fdw.c index 33a37d832ce..a60fb226320 100644 --- a/contrib/file_fdw/file_fdw.c +++ b/contrib/file_fdw/file_fdw.c @@ -36,6 +36,7 @@ #include "optimizer/pathnode.h" #include "optimizer/planmain.h" #include "optimizer/restrictinfo.h" +#include "utils/backend_status.h" #include "utils/acl.h" #include "utils/memutils.h" #include "utils/rel.h" @@ -119,6 +120,16 @@ typedef struct FileFdwExecutionState CopyFromState cstate; /* COPY execution state */ } FileFdwExecutionState; +/* + * Since progress tracking of multiple COPY commands is not supported, the + * first file_fdw node of the plan needs to set pgstat_track_activities to + * false during startup, and the last active node needs to restore the + * original value during shutdown. + */ +static bool save_pgstat_track_activities = false; +static int fdw_nodes = 0; +static int active_fdw_nodes = 0; + /* * SQL functions */ @@ -616,6 +627,12 @@ fileGetForeignPlan(PlannerInfo *root, { Index scan_relid = baserel->relid; + /* + * This seems to be the appropriate place to count file_fdw nodes in the + * plan. + */ + fdw_nodes++; + /* * We have no native ability to evaluate restriction clauses, so we just * put all the scan_clauses into the plan node's qual list for the @@ -695,6 +712,18 @@ fileBeginForeignScan(ForeignScanState *node, int eflags) /* Add any options from the plan (currently only convert_selectively) */ options = list_concat(options, plan->fdw_private); + /* + * Save the value of pgstat_track_activities if this is the first file_fdw + * node of a plan containing multiple file_fdw nodes, and disable the + * progress tracking. The monitoring infrastructure currently does not + * support monitoring of multiple COPY commands. + */ + if (fdw_nodes > 1 && active_fdw_nodes++ == 0) + { + save_pgstat_track_activities = pgstat_track_activities; + pgstat_track_activities = false; + } + /* * Create CopyState from FDW options. We always acquire all columns, so * as to match the expected ScanTupleSlot signature. @@ -861,6 +890,21 @@ fileEndForeignScan(ForeignScanState *node) festate->cstate->num_errors)); EndCopyFrom(festate->cstate); + + + /* + * Restore the value of pgstat_track_activities if this is the last + * file_fdw node of a plan containing multiple file_fdw nodes, and enable + * progress tracking if we disabled it earlier. + */ + if (active_fdw_nodes > 0) + { + if (--active_fdw_nodes == 0) + { + pgstat_track_activities = save_pgstat_track_activities; + fdw_nodes = 0; + } + } } /* diff --git a/src/backend/commands/indexcmds.c b/src/backend/commands/indexcmds.c index 9ab74c8df0a..7280e64d118 100644 --- a/src/backend/commands/indexcmds.c +++ b/src/backend/commands/indexcmds.c @@ -3918,6 +3918,12 @@ ReindexRelationConcurrently(const ReindexStmt *stmt, Oid relationOid, const Rein * more detailed comments. */ + /* + * XXX Is there a reason not to start progress reporting here? If it's ok, + * then INDEX_CREATE_SUPPRESS_PROGRESS below is probably not needed. + */ + pgstat_progress_start_command(PROGRESS_COMMAND_CREATE_INDEX, relationOid); + foreach(lc, indexIds) { char *concurrentName; @@ -3966,8 +3972,6 @@ ReindexRelationConcurrently(const ReindexStmt *stmt, Oid relationOid, const Rein if (indexRel->rd_rel->relpersistence == RELPERSISTENCE_TEMP) elog(ERROR, "cannot reindex a temporary table concurrently"); - pgstat_progress_start_command(PROGRESS_COMMAND_CREATE_INDEX, idx->tableId); - progress_vals[0] = PROGRESS_CREATEIDX_COMMAND_REINDEX_CONCURRENTLY; progress_vals[1] = 0; /* initializing */ progress_vals[2] = idx->indexId; @@ -4144,7 +4148,6 @@ ReindexRelationConcurrently(const ReindexStmt *stmt, Oid relationOid, const Rein * Update progress for the index to build, with the correct parent * table involved. */ - pgstat_progress_start_command(PROGRESS_COMMAND_CREATE_INDEX, newidx->tableId); progress_vals[0] = PROGRESS_CREATEIDX_COMMAND_REINDEX_CONCURRENTLY; progress_vals[1] = PROGRESS_CREATEIDX_PHASE_BUILD; progress_vals[2] = newidx->indexId; @@ -4208,7 +4211,6 @@ ReindexRelationConcurrently(const ReindexStmt *stmt, Oid relationOid, const Rein * Update progress for the index to build, with the correct parent * table involved. */ - pgstat_progress_start_command(PROGRESS_COMMAND_CREATE_INDEX, newidx->tableId); progress_vals[0] = PROGRESS_CREATEIDX_COMMAND_REINDEX_CONCURRENTLY; progress_vals[1] = PROGRESS_CREATEIDX_PHASE_VALIDATE_IDXSCAN; progress_vals[2] = newidx->indexId; diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c index 9d162957bc3..f360f37a9da 100644 --- a/src/backend/commands/repack.c +++ b/src/backend/commands/repack.c @@ -1937,6 +1937,7 @@ finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, pgstat_progress_update_param(PROGRESS_REPACK_PHASE, PROGRESS_REPACK_PHASE_REBUILD_INDEX); + reindex_params.options |= REINDEXOPT_REPORT_PROGRESS; reindex_relation(NULL, OIDOldHeap, reindex_flags, &reindex_params); } @@ -3204,9 +3205,20 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) "repacknew", get_rel_namespace(ind->rd_index->indrelid), false); - newindex = index_create_copy(NewHeap, INDEX_CREATE_SUPPRESS_PROGRESS, + + /* + * We build the index on the new heap, but after the swap phase it'll + * become an index on the old heap. It makes more sense to report the + * progress this way. (The reporting API expects that both command and + * subcommand deal with the same target.) + */ + pgstat_progress_start_command(PROGRESS_COMMAND_CREATE_INDEX, + RelationGetRelid(OldHeap)); + newindex = index_create_copy(NewHeap, 0, oldindex, ind->rd_rel->reltablespace, newName); + pgstat_progress_end_command(); + copy_index_constraints(ind, newindex, RelationGetRelid(NewHeap)); result = lappend_oid(result, newindex); diff --git a/src/backend/utils/activity/backend_progress.c b/src/backend/utils/activity/backend_progress.c index b0359771de5..97965a6973c 100644 --- a/src/backend/utils/activity/backend_progress.c +++ b/src/backend/utils/activity/backend_progress.c @@ -22,6 +22,10 @@ * * Set st_progress_command (and st_progress_command_target) in own backend * entry. Also, zero-initialize st_progress_param array. + * + * If command has already been started, start a sub-command. Only parameters + * of the sub-command are updated until pgstat_progress_end_command() is + * called. (Target relation must be the same for both commands.) *----------- */ void @@ -33,9 +37,30 @@ pgstat_progress_start_command(ProgressCommandType cmdtype, Oid relid) return; PGSTAT_BEGIN_WRITE_ACTIVITY(beentry); - beentry->st_progress_command = cmdtype; - beentry->st_progress_command_target = relid; - MemSet(&beentry->st_progress_param, 0, sizeof(beentry->st_progress_param)); + /* Sub-command should not be started w/o parent command. */ + if (beentry->st_progress_command == PROGRESS_COMMAND_INVALID) + { + Assert(beentry->st_progress_command2 == PROGRESS_COMMAND_INVALID); + + beentry->st_progress_command = cmdtype; + beentry->st_progress_command_target = relid; + MemSet(&beentry->st_progress_param, 0, + sizeof(beentry->st_progress_param)); + } + else if (beentry->st_progress_command2 == PROGRESS_COMMAND_INVALID) + { + Assert(beentry->st_progress_command != PROGRESS_COMMAND_INVALID); + Assert(beentry->st_progress_command_target == relid); + + beentry->st_progress_command2 = cmdtype; + MemSet(&beentry->st_progress_param2, 0, + sizeof(beentry->st_progress_param2)); + } + else + { + /* Only one level of nesting is supported. */ + Assert(false); + } PGSTAT_END_WRITE_ACTIVITY(beentry); } @@ -49,14 +74,20 @@ void pgstat_progress_update_param(int index, int64 val) { volatile PgBackendStatus *beentry = MyBEEntry; + volatile int64 *params; Assert(index >= 0 && index < PGSTAT_NUM_PROGRESS_PARAM); + Assert(beentry->st_progress_command != PROGRESS_COMMAND_INVALID || + beentry->st_progress_command2 != PROGRESS_COMMAND_INVALID); if (!beentry || !pgstat_track_activities) return; + params = (beentry->st_progress_command2 == PROGRESS_COMMAND_INVALID) ? + beentry->st_progress_param : beentry->st_progress_param2; + PGSTAT_BEGIN_WRITE_ACTIVITY(beentry); - beentry->st_progress_param[index] = val; + params[index] = val; PGSTAT_END_WRITE_ACTIVITY(beentry); } @@ -70,14 +101,20 @@ void pgstat_progress_incr_param(int index, int64 incr) { volatile PgBackendStatus *beentry = MyBEEntry; + volatile int64 *params; Assert(index >= 0 && index < PGSTAT_NUM_PROGRESS_PARAM); + Assert(beentry->st_progress_command != PROGRESS_COMMAND_INVALID || + beentry->st_progress_command2 != PROGRESS_COMMAND_INVALID); if (!beentry || !pgstat_track_activities) return; + params = (beentry->st_progress_command2 == PROGRESS_COMMAND_INVALID) ? + beentry->st_progress_param : beentry->st_progress_param2; + PGSTAT_BEGIN_WRITE_ACTIVITY(beentry); - beentry->st_progress_param[index] += incr; + params[index] += incr; PGSTAT_END_WRITE_ACTIVITY(beentry); } @@ -124,17 +161,24 @@ pgstat_progress_update_multi_param(int nparam, const int *index, { volatile PgBackendStatus *beentry = MyBEEntry; int i; + volatile int64 *params; if (!beentry || !pgstat_track_activities || nparam == 0) return; + Assert(beentry->st_progress_command != PROGRESS_COMMAND_INVALID || + beentry->st_progress_command2 != PROGRESS_COMMAND_INVALID); + + params = (beentry->st_progress_command2 == PROGRESS_COMMAND_INVALID) ? + beentry->st_progress_param : beentry->st_progress_param2; + PGSTAT_BEGIN_WRITE_ACTIVITY(beentry); for (i = 0; i < nparam; ++i) { Assert(index[i] >= 0 && index[i] < PGSTAT_NUM_PROGRESS_PARAM); - beentry->st_progress_param[index[i]] = val[i]; + params[index[i]] = val[i]; } PGSTAT_END_WRITE_ACTIVITY(beentry); @@ -144,7 +188,7 @@ pgstat_progress_update_multi_param(int nparam, const int *index, * pgstat_progress_end_command() - * * Reset st_progress_command (and st_progress_command_target) in own backend - * entry. This signals the end of the command. + * entry. This signals the end of the command (or a sub-command). *----------- */ void @@ -155,11 +199,19 @@ pgstat_progress_end_command(void) if (!beentry || !pgstat_track_activities) return; - if (beentry->st_progress_command == PROGRESS_COMMAND_INVALID) - return; - PGSTAT_BEGIN_WRITE_ACTIVITY(beentry); - beentry->st_progress_command = PROGRESS_COMMAND_INVALID; - beentry->st_progress_command_target = InvalidOid; + + if (beentry->st_progress_command2 != PROGRESS_COMMAND_INVALID) + { + Assert(beentry->st_progress_command != PROGRESS_COMMAND_INVALID); + + beentry->st_progress_command2 = PROGRESS_COMMAND_INVALID; + } + else + { + beentry->st_progress_command = PROGRESS_COMMAND_INVALID; + beentry->st_progress_command_target = InvalidOid; + } + PGSTAT_END_WRITE_ACTIVITY(beentry); } diff --git a/src/backend/utils/activity/backend_status.c b/src/backend/utils/activity/backend_status.c index d685fc5cd87..15675992415 100644 --- a/src/backend/utils/activity/backend_status.c +++ b/src/backend/utils/activity/backend_status.c @@ -284,6 +284,7 @@ pgstat_bestart_initial(void) lbeentry.st_state = STATE_STARTING; lbeentry.st_progress_command = PROGRESS_COMMAND_INVALID; + lbeentry.st_progress_command2 = PROGRESS_COMMAND_INVALID; lbeentry.st_progress_command_target = InvalidOid; lbeentry.st_query_id = INT64CONST(0); lbeentry.st_plan_id = INT64CONST(0); diff --git a/src/backend/utils/adt/pgstatfuncs.c b/src/backend/utils/adt/pgstatfuncs.c index 7a9dfa9ba3b..c2257d900af 100644 --- a/src/backend/utils/adt/pgstatfuncs.c +++ b/src/backend/utils/adt/pgstatfuncs.c @@ -314,6 +314,7 @@ pg_stat_get_progress_info(PG_FUNCTION_ARGS) Datum values[PG_STAT_GET_PROGRESS_COLS] = {0}; bool nulls[PG_STAT_GET_PROGRESS_COLS] = {0}; int i; + volatile int64 *params; local_beentry = pgstat_get_local_beentry_by_index(curr_backend); beentry = &local_beentry->backendStatus; @@ -322,7 +323,11 @@ pg_stat_get_progress_info(PG_FUNCTION_ARGS) * Report values for only those backends which are running the given * command. */ - if (beentry->st_progress_command != cmdtype) + if (beentry->st_progress_command == cmdtype) + params = beentry->st_progress_param; + else if (beentry->st_progress_command2 == cmdtype) + params = beentry->st_progress_param2; + else continue; /* Value available to all callers */ @@ -334,7 +339,7 @@ pg_stat_get_progress_info(PG_FUNCTION_ARGS) { values[2] = ObjectIdGetDatum(beentry->st_progress_command_target); for (i = 0; i < PGSTAT_NUM_PROGRESS_PARAM; i++) - values[i + 3] = Int64GetDatum(beentry->st_progress_param[i]); + values[i + 3] = Int64GetDatum(params[i]); } else { diff --git a/src/include/utils/backend_status.h b/src/include/utils/backend_status.h index a334e096e4a..f528f7abeec 100644 --- a/src/include/utils/backend_status.h +++ b/src/include/utils/backend_status.h @@ -169,6 +169,13 @@ typedef struct PgBackendStatus Oid st_progress_command_target; int64 st_progress_param[PGSTAT_NUM_PROGRESS_PARAM]; + /* + * Some commands have a sub-command, e.g. REPACK (re)builds indexes. The + * subcommands are supposed to have the same target. + */ + ProgressCommandType st_progress_command2; + int64 st_progress_param2[PGSTAT_NUM_PROGRESS_PARAM]; + /* query identifier, optionally computed using post_parse_analyze_hook */ int64 st_query_id; -- 2.47.3 --=-=-=-- ^ permalink raw reply [nested|flat] 403+ messages in thread
end of thread, other threads:[~2026-05-04 09:32 UTC | newest] Thread overview: 403+ messages (download: mbox mbox.gz follow: Atom feed) -- links below jump to the message on this page -- 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera 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cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera 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cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera 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cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera 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cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera 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cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera 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cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera 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cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera 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cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera 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cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-05-04 09:32 [PATCH] Allow progress tracking of sub-commands. Antonin Houska <ah@cybertec.at>
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